Chemotaxis of tumor cells will be studied in the agarose system. Comparisons will be made between the behavior of fibroblasts and fibrosarcoma cells. Cultured malignant cells (Novikoff and Walker cells) will be examined for chemotactic function. Finally, studies will be continued to define chemically the nature of the C5 fragment that is chemotactic for tumor cells. BIBLIOGRAPHIC REFERENCES: Romualdez, A. G., and Ward, P. A. 1976. Further studies of the C5-derived chemotactic factor for tumor cells. In "Membrane and Neoplasia: New Approaches and Strategies." Ed. by V. T. Marchesi, Publ. by A. R. Liss Inc. (N.Y.), pg. 65-71. Romuladez, A. G., Ward, P. A. and Torikata, T. 1976. Relationship between the C5 peptides chemotactic for leukocytes and tumor cells. J. Immunol. 117: 1762-1766.